JPH09285809A - Looper controller for continuous rolling mill - Google Patents

Abstract

(57) Abstract: A looper angle and a looper angular velocity are measured as actual values of a rolling mill, and based on these, a decrease in responsiveness of a control system due to a change in angular velocity due to angle control of a looper is prevented. SOLUTION: A roll speed change amount ΔV ^REF for eliminating an angular deviation Δθ between a looper angle θ and a target angle θ ^REF is calculated by a looper height control unit 12, and this roll speed change amount Δ.
Based on V ^REF , the target angular velocity ω ^REF that can obtain good response characteristics when changing the peripheral velocity of the roll according to the roll velocity change amount ΔV ^REF is used as the reference model forming unit 14
Then, the velocity correction amount ΔVω for eliminating the disturbance Δω which is the deviation between the target angular velocity ω ^REF and the actual angular velocity ω is calculated. Then, the roll speed change amount ΔV ^REF and the speed correction amount ΔVω are added, and this is output as the speed change command value ΔV ^* to the speed control unit 17, and the peripheral speed of the roll is changed based on this speed change command value ΔV ^*. To do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a looper controller mainly used in a continuous rolling mill such as a hot rolling finishing mill.

[0002]

2. Description of the Related Art Usually, a looper is arranged between each stand of a hot continuous rolling mill and has a function of stably maintaining a loop amount of the rolled material and a tension of the rolled material between the stands. The method of compensating for the fluctuation of the angular velocity caused by the disturbance of the line velocity, such as immediately after the stand top biting of the rolled material, is performed by performing the constant angle control.

As a control method of this constant angle control, there is a method of measuring the looper angle and correcting the peripheral speed of the roll so as to eliminate the difference between the measured looper angle and a preset target value of the looper angle. It has been known. For example, in the looper control device described in Japanese Patent Application Laid-Open No. 56-47209 (hereinafter referred to as the first conventional example), the looper angle is measured, and the entrance side and the exit side of the rolled material are measured based on the measured looper angle. The speed inconsistency between the stands is calculated, and the peripheral speed of the roll is changed and adjusted to eliminate this difference.

Further, for example, Japanese Patent Laid-Open No. 61-222621
In the looper control device described in Japanese Patent Publication (hereinafter referred to as the second conventional example), the looper constant control for adjusting the speed of the mill motor based on the looper angle deviation is used as a minor loop, and the constant angular velocity control for making the angular velocity constant is used as a minor loop. The output of the looper constant height control is used as the target angular velocity of the constant angular velocity control, and the looper constant angle control is performed based on the looper angle and the looper angular velocity.

[0005]

In the above-mentioned first conventional looper control device, only the looper angle is measured and the peripheral speed of the roll is corrected based on only this looper angle. As the actual value of, the looper angle is controlled only based on the looper angle, but the followability of the looper angle to the target angle, the occurrence of overshoot, etc.
The response characteristics of the control system were insufficient.

Further, in the looper control device of the second conventional example, since the minor loop is connected in cascade to the main loop for performing constant looper height (looper angle) control, the main loop and the minor loop are connected. It could not be adjusted independently, and sufficient response characteristics of the control system could not be obtained.

Therefore, the present invention has been made by paying attention to the above-mentioned conventional problems, and improves the responsiveness in angle control of the looper to stabilize the looper angle, and manufactures a rolled material with good dimensional accuracy. An object of the present invention is to provide a looper control device for a continuous rolling mill capable of performing the above.

[0008]

In order to achieve the above object, a looper control device for a continuous rolling mill according to the present invention arranges loopers between stands each having rolls, and a real angle and a target angle of the loopers. Based on the angular deviation from the, the peripheral speed change amount of the roll is set, and the peripheral speed of the roll is adjusted according to the peripheral speed change amount so that the actual angle matches the target angle. In a looper control device of a continuous rolling mill, a target angular velocity of a looper capable of matching the actual angle to the target angle with a predetermined response characteristic, and a target angular velocity of the looper preset according to the angular deviation. It is characterized in that a correction means for correcting the peripheral speed change amount is provided so as to match the real angular velocities of the looper.

According to the looper control device of the continuous rolling mill of the present invention, the peripheral speed change amount of the roll is set based on the angular deviation between the actual angle of the looper and the target angle, and the peripheral speed change amount is set according to this peripheral speed change amount. The peripheral speed of the roll is adjusted. At this time, the target angular velocity that can be matched with a predetermined response characteristic when matching the actual angle of the looper with the target angle set in advance depends on a value based on the angular deviation such as the peripheral speed change amount. The peripheral velocity change amount is corrected based on the detected angular velocity deviation between the target angular velocity and the actual angular velocity. Therefore,
For example, if the target angular velocity is set in advance so that it can be controlled with an ideal response characteristic, disturbance such as a change in angular velocity associated with the angle control is removed, and the angle control is performed with a preset ideal response characteristic.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a block diagram showing an example of a looper control device for a continuous rolling mill according to the present invention.

In the figure, i and i + 1 are two adjacent stands, 1 is a looper, and 2 is a rolled material. The looper 1 is between the stands i and i + 1, presses the rolled material 2 passed from the left side in FIG. 1 upward from the contact surface side with the looper 1, and imparts an appropriate tension to the rolled material 2, An appropriate loop amount of the rolled material 2 is secured between the stands i and i + 1.

The looper 1 is constructed by connecting a base end of a looper arm 1b pivotally supporting a roller 1a to a looper motor 3 such as a hydraulic or electric motor. The looper arm 1b moves upward from a horizontal position. The looper angle (actual angle of the looper) θ and the looper angular velocity ω (the angular velocity of the looper) ω, which are the rotation angles of, are detected by the angle detector 4 and the angular velocity detector 5 laid on the looper angle. The angle detector 4 is composed of a synchro or pulse generator or the like, and the angular velocity detector 5 is composed of a tacho generator or the like.

Then, the looper angle θ detected by the angle detector 4 is input to the calculator 11, which calculates the difference between the preset looper target angle θ ^REF and the looper angle θ to obtain the angle deviation. It is output to the looper height control unit 12 as Δθ (= θ−θ ^REF ). The looper height control unit 12 calculates a roll speed change amount (circumferential speed change amount) ΔV ^REF for eliminating the angle deviation Δθ based on the angle deviation Δθ, and outputs this to the calculator 13. , To the reference model forming unit 14.

In the reference model forming unit 14, the roll speed change amount ΔV is calculated based on a preset reference model.
^The angular velocity corresponding to ^REF is detected, and this is determined as the target angular velocity ω
^It is output to the calculator 15 as ^REF .

The target angular velocity ω ^REF is defined as the roll velocity change amount ΔV ^REF , which is an angular velocity that can obtain an arbitrarily set response characteristic when the angle of the looper 1 is controlled based on the roll velocity change amount ΔV ^REF . The values are set in correspondence with each other, and are set based on the following equation, for example.

Ω ^REF = {d / (as ² + bs + c)} · ΔV ^{REF In the} calculator 15, the input target angular velocity ω ^REF and
The looper angular velocity ω from the angular velocity detector 5 is input, and the deviation between them is calculated and output to the velocity correction unit 16 as a disturbance Δω (= ω ^REF −ω). In this speed correction unit 16,
Based on the input disturbance Δω, a speed correction amount ΔVω for canceling this disturbance Δω is calculated, and this is calculated by the arithmetic unit 1
Output to 3.

Then, the computing unit 13 adds the roll speed change amount ΔV ^REF and the speed correction amount ΔVω, and outputs it as a speed change command value ΔV ^* (= ΔV ^REF + ΔVω) to the speed control unit 17. The speed control unit 17 corrects the roll speed setting value set in advance according to the input speed change command value ΔV ^* , and determines the control amount for the rolling mill motor 20 required to realize the corrected speed setting value. Along with the calculation, a control signal corresponding to this is output to the rolling mill motor 20.

As a result, the rotation speed of the rolling mill motor 20 is adjusted, the rotation speed of the roll is adjusted, and the rolling material 2
The looper angle is controlled according to the change in tension of the looper. here,
The arithmetic unit 13, the reference model forming unit 14, the arithmetic unit 15, and the speed correction unit 16 correspond to the correction means.

The looper motor 3 is controlled by, for example, a tension control device (not shown), and for example, the tension of the rolled material 2 is calculated based on the looper angular velocity ω of the looper arm 1b and compared with a preset tension command value. The tension deviation is obtained, and the looper motor 3 is drive-controlled in accordance with the torque correction amount for eliminating the tension deviation, so that a predetermined tension is applied to the rolled material 2.

Next, the operation of the above embodiment will be described.
Now, it is assumed that the angle θ of the looper arm 1b matches a preset target angle θ ^REF, and the rolled material 2 is passed through while maintaining a predetermined tension. In this case, since the looper angle θ and the target angle θ ^REF match, the angle deviation Δ
θ becomes zero, and the speed correction amount ΔVω becomes zero. Therefore,
The roll speed is not corrected, and the rolling mill motor 20 is drive-controlled based on a preset predetermined roll speed setting value.

From this state, the tension of the rolled material 2 changes due to, for example, a setting error of the roll speed between the stands, and when the tension becomes strong, the looper angle θ becomes the target angle θ.
^{When the} tension becomes smaller than ^REF , and conversely the tension becomes smaller, the looper angle θ becomes larger than the target angle θ ^REF . The difference between the looper angle θ and the target angle θ ^REF is detected as the angle deviation Δθ, and the roll speed change amount ΔV ^REF that can eliminate the angle deviation Δθ is calculated.

When changing the roll speed by the roll speed change amount ΔV ^REF , the ideal response characteristic, that is, the response characteristic of the looper angle θ accompanying the change of the roll speed for eliminating the angular deviation, is exceeded. The shoot is small,
A target angular velocity ω ^REF is set according to the roll velocity change amount ΔV ^REF that can be controlled so that the response characteristic of the looper angle θ is small. Then, the speed correction amount ΔVω capable of eliminating the disturbance Δω which is the deviation between the target angular velocity ω ^REF and the looper angular velocity ω is calculated, and the roll speed change amount ΔV ^REF and the disturbance Δω for eliminating the angular deviation Δθ are eliminated. The roll speed change amount ΔV ^* is set based on the speed correction amount ΔVω.

Therefore, by controlling the rolling mill motor 20 on the basis of the roll speed change amount ΔV ^* thus set, the angle deviation θ is eliminated and the looper for eliminating the angle deviation θ. The disturbance Δω due to the change in the angular velocity accompanying the angle control is estimated, and this disturbance Δω
The looper angle is controlled so as to eliminate ω as well. Then, at this time, the target angular velocity ω ^REF is set to a value that can be a preset ideal response characteristic, so that the response characteristic of the looper angle follows the ideal response characteristic, and thus the looper angle control is performed. It is possible to avoid the influence of the accompanying disturbance and improve the disturbance suppression characteristic of the system. Therefore, it is possible to reduce the overshoot and stabilize the looper angle fluctuation by reducing it. Therefore, the followability of the looper angle θ with the target angle θ ^REF is improved and the looper angle θ is made to match the target value at an earlier stage. It is possible to improve controllability and obtain stable and highly responsive control characteristics.

Therefore, since the looper angle control can be controlled with high precision and high response, uniform rolling can be performed, and dimensional precision such as strip pressure and strip width of the rolled material is improved. be able to.

Further, even when the looper angle suddenly changes, such as when slipping through the bottom of the threading plate, the preset target angular velocity ω ^REF is followed, so that large fluctuations in the looper angular velocity are prevented and stability is improved. And stable tension can be obtained.

The looper angle θ is used as the actual value of the rolling mill.
And the looper angular velocity ω are measured, and the looper angle θ is controlled based on these, so that more accurate control according to the state of the rolling mill can be performed, more stable, and It is possible to perform looper angle control with high responsiveness.

Furthermore, looper angle θ and the target angle θ roll speed change amount capable eliminate angular deviation Δθ between the ^REF [Delta] V ^REF
On the other hand, the roll speed change amount ΔV is obtained by adding up the speed correction amount ΔVω for canceling the looper angular velocity disturbance Δω due to the roll speed change for eliminating the angular deviation Δθ.
^{Since *} is set, the gain of the speed correction unit 16 can be adjusted when the actual machine is applied, and the adjustment for the disturbance and the angular deviation of the looper can be performed independently, so that the accurate adjustment according to the actual machine is possible. It is possible to control the looper angle.

In the above embodiment, the case of applying the tension control plate width control between two stands has been described, but the present invention is not limited to this, and the same control is performed even when three stands or more. It can be carried out.

Further, in the above embodiment, the case where the target angular velocity ω ^REF is set by the reference model forming unit 14 based on the roll velocity change amount ΔV ^REF has been described, but the target angular velocity ω ^REF is set based on the angular deviation Δθ. It is also possible to set the angular velocity, and it is possible to obtain the same effects as the above.

Further, in the above embodiment, in the case where the target angular velocity ω ^REF is set so that the response characteristic of the transfer function based on the roll velocity change amount ΔV ^REF becomes the second-order lag characteristic in the above embodiment. I explained about
The present invention is not limited to this, and may exhibit, for example, a first-order delay characteristic, a proportional characteristic, or other high-order delay characteristic.

[0031]

EXAMPLE A step response of looper angle control was compared between the looper control device of the present invention and a conventional looper control device. FIG. 2 shows the response characteristic of the looper control device of the present invention, and FIG. 3 shows the response characteristic of the looper control device.

As can be seen from FIG. 2 and FIG. 3, the responsiveness is superior to the conventional one, the overshoot is greatly reduced and the fluctuation thereof is reduced, and the stable and steep target value tracking characteristic can be achieved. It was confirmed that it was possible.

[0033]

As described above, according to the looper controller of the continuous rolling mill of the present invention, the peripheral speed change amount of the roll is set based on the angular deviation between the actual angle of the looper and the target angle. Further, in order to eliminate the angular deviation, a target angular velocity that can obtain a preset predetermined response characteristic is obtained, and the peripheral velocity change amount is corrected so that the actual angular velocity follows the target angular velocity. The looper angle can be controlled with stable and steep response characteristics by removing disturbances such as changes in angular velocity due to angle control. Therefore, the variation of the looper angle is prevented, so that a rolled material with high dimensional accuracy can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a looper control device for a continuous rolling mill of the present invention.

FIG. 2 is a characteristic diagram showing a step response characteristic of a looper angle by a looper control device of a continuous rolling mill of the present invention.

FIG. 3 is a characteristic diagram showing a step response characteristic of a looper angle by a looper control device of a conventional continuous rolling mill.

[Explanation of symbols]

1 looper 2 rolled material 3 looper motor 4 angle detector 5 angular velocity detector 12 looper height control unit 14 normative model forming unit 16 speed correction unit 20 rolling mill motor i, i + 1 stand θ looper angle θ ^REF target angle ω looper angular velocity ω ^REF Target angular velocity

Claims (1)

[Claims] 1. A looper is arranged between stands each having a roll, and a peripheral speed change amount of the roll is set based on an angular deviation between a real angle of the looper and a target angle, and the peripheral speed change amount is set. In the looper control device of the continuous rolling mill, which adjusts the peripheral speed of the roll according to to match the actual angle with the target angle, to match the actual angle with the target angle with a predetermined response characteristic. A target angular velocity of the looper capable of being adjusted, and a correction unit that corrects the peripheral speed change amount so that the actual angular velocity of the looper matches the preset target angular velocity of the looper according to the angular deviation. Looper control device for continuous rolling mill.